I think the height of the Prince of Sweden is 1m83cm, I remember I found this from a website, but cannot remember which web. Anyway, I will try to find out and let you know. So, he is the tallest one?!

Per the Monarchy's website the Queen is 5'4", Prince
Harry is 6'2", Prince William is 6'3". These are the
only heights I could find verified at the official
website.
Other heights found elsewhere on the web:
Prince Philip 5'11 1/2", Prince Charles 5'11",
Princess Anne 5'6 1/2", Prince Andrew 6', Prince
Edward 6'.

Per the Monarchy's website the Queen is 5'4", Prince
Harry is 6'2", Prince William is 6'3". These are the
only heights I could find verified at the official
website.
Other heights found elsewhere on the web:
Prince Philip 5'11 1/2", Prince Charles 5'11",
Princess Anne 5'6 1/2", Prince Andrew 6', Prince
Edward 6'.

But at the bottom of the page they note that the vital statistics of royals women are only estimates. I guess they measure the men and only estimate the women. Maybe they are only when they have heels on.

I believe Diana was 5'11", Charles may be 5'10"-ish. All the British royals look tall...I think Beatrice may be around 5'6" and Eugenie 5'6 1/2"...she's probably still growing though. The queen's shrinking (:P) but she may have been taller in her youth. Harry and William are 6'2" and 6'3" respectively.